In the production of frozen ice cream mass with solid ingredients, it is well-known to use an auger conveyor for conveying the solid ingredients from a hopper to a pump, which may for instance be a lamella pump or a piston pump, by means of which the solid ingredients are mixed into a flow of ice cream mass.
It is also known to use auger conveyors having augers with increasing pitch and/or decreasing core diameter along the direction of conveyance. This results in an increasing volume along the auger, which assures that the amount of solid ingredients entering the auger conveyor is more evenly distributed across the hopper, whereas an auger with a constant pitch and core diameter will typically be filled shortly after its starting point, meaning that almost no ingredients will be drawn from the other side of the hopper.
However, even with such measures having been taken, it has proven to be difficult to avoid clogging and lumping of the ingredients and damage to fragile types of ingredients, especially at the outlet from the hopper to the auger conveyor, which in turn results in an uneven dosing of the ingredients at the end of the auger conveyor.